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2 Février 2010
E. Gaffet
Nanomaterials Research Group - CNRS - Belfort
Nano Argent / Nano Silver
Argent : Silver
● Production Industrielle (+ 30% de 1999 à 2007)
1999 : 15.500 Tonnes /Mexique et US – 2007 : 20.500 Tonnes (mondial NanoPen 15)
Dispersion environnement (US) : 2.500 Tonnes (S “Ag”) 29% dans l’eau, 68 % dans la terre
http://www.nanolawreport.com/2008/07/articles/nanosilver-ehs-backgrounder/ (Juillet 2008)
Production n-Ag mondiale : 500 Tonnes / an
http://www.oracwa.org/files/news/415/OChoi-Impact-of-Silver-Nano-particles.pdf (citant Mueller et Novack - 2008)
The Silver Institute (2001) estimated that the use of silver as a biocide would
increase by about 500 times between 2000 and 2004 in Europe
(with an estimate of 30 t/yr for 2004)
S. A. Blaser, M. Scheringer, M. MacLeod, K. Hungerbühler
Science of the Total Environment - 390 (2008) 396 – 409
The European market for silver-containing products is projected to reach 110–230 t
of silver by 2010 (x 4 – x 8) and stabilization is expected for approximately 2015
(Hei, 2006 )
Nano-silver contributes 0.3-15% to the total Ag flow
In 2010, biocidal plastics and textiles are predicted to account for up to 15% of the total
silver released into water in the European Union.
Blaser, S. A., M. Scheringer, et al. - Science of the Total Environment 390(2-3) (2008) 396-409.
Source : Bernd Nowack - http://www.wsl.ch/events/research_seminar/rs_2009/pres-nowack.pdf
Types of Colloidal Silver
The three types of products that consumers find
labeled as “colloidal silver”
can be categorized as follows:
ionic silver solutions ,
silver protein,
true colloidal silver .
Inventaire : http://www.google.com/search?hl=en&q=colloidal+silver+products
Metal Content
Product Name
Percent of Labeled Value
Click on product name for complete lab analysis report
>>> 0.03 <<<
WEE - Detoxing Mineral Water 1000 ppm
>>> 0.09 <<<
Nano-2 Silver 2000 ppm
>>> 0.52 <<< Earthborn Products - Colloidal Silver 100 ppm
>>> 1.7 <<< Health & Herbs Colloidal Silver 10 ppm
20.5 Solutions IE Colloidal Silver Plus 20 ppm
47.1 Golden Touch Mfg. Ultra Pure Colloidal Silver 35 ppm
68.3 Argentyn 23 ppm
81.0 Survival Enterprises Silver Water 3 ppm
81.0 Silver Water Products - Silver Wain Water 3 ppm
91.2 Silver Lightning Tonic Water 5 ppm
95.4 Tri Silver Colloidal Silver 10 ppm
97.1 Sovereign Silver 10 ppm
99.5 "Wonder Water" Silver Fortified Water 10 ppm
101.4 ASAP Solution 22 ppm
106.0 Daily Mfg., Inc 20 ppm
106.0 Trace Minerals - Liqumins Colloidal Silver 30 ppm
109.3 Silver Biotics 10 ppm
110.2 ASAP Solution 10 ppm
133 TriMedica Silva Solution 10 ppm
140 High Energy Labs Colloidal Silver 15 ppm
264
….
InSpiral Technologies Electra Clear Colloidal Silver 5-10 ppm
…..
Percent of Metal Content Table
In the table below, the Metal Content indicates the accuracy of product
labeling. A value of 100 percent means the label accurately describes the metal
content of the product. Values near zero indicate that the product contains very
little or none of the metal content indicated on the label.
http://www.nano-
size.com/pictures%20for%20products/pdf%2
0files/Nano_Ag%2050nm.pdf
http://silver-
colloids.com/Reports/SEM
-Images.html
Two SEM images of silver particles in "mild
silver protein" powder - Gelatine
500nm
True colloidal silver products are the least prevalent type of colloidal silver on the market
due to high degree of manufacturing complexity and the resulting high cost of production.
In true colloidal silver, the majority of the silver content is in the form of silver particles.
True colloids will typically contain more than 50%
particles (often 50 – 80%), while the balance (20% to 49%)
will be silver ions. When referring to colloidal silver, the word colloid means silver
particles. The two critical factors to look for in determining true colloids are the percentage
of silver particles and the particle surface area.
Of all the types of silver marketed as colloidal, true colloidal silver products have the
highest particle surface area. High particle surface area is achieved by a high percentage of
silver particles combined with very small sized particles. Of the three types of silver on the
market, true silver colloids have the highest particle surface area relative to the total silver
content. The ratio of particle surface area to total silver content indicates how efficiently the
colloid is able to produce particle surface area which determines effectiveness. Higher
conversion efficiencies are more desirable.
The nanometer-sized particles in true silver colloids remain in colloidal suspension without
requiring protein or other additives. It is the mutual repulsion of the particles created by
the zeta potential charge that keeps the particles uniformly distributed in the colloid.
•True Colloidal Silver
http://www.silver-colloids.com/Reports/reports.html#true
S.C. Tjong, Haydn Chen - Materials Science and Engineering R 45 (2004) 1–88
Tollens Synthesis
V.K. Sharma et al.
Advances in Colloid and Interface Science 145 (2009) 83–96
Jinhu Yang, Limin Qi,* Conghua Lu, Jiming Ma, and
Humin ChengAngew. Chem. Int. Ed. 2005, 44, 598 –603
http://www.nano-
size.com/pictures%20for%20products/pdf%2
0files/Nano_Ag%2050nm.pdf
http://www.nano-
size.com/pictures%20for%20products/pdf%20
files/Nano_Ag%20Powder%2050nm.pdf
http://www.ec21.com/ec-market/nano_silver.html
Results for nano silver : 526 Products from 264 Companies.
NanoProducts / Nano Silver
http://www.iom.edu/Object.File/Master/62/475/Martin%20Philbert.pdf
< 1 Tonne / An / Producteur
Reach ???
http://www.nanotechproject.org/inventories/consumer/analysis_draft/
Mise à jour en date du 21 Août 2008
Figure 4. Numbers of products associated with specific materials.
As Figure 4 indicates, there is a small set of materials explicitly referenced in nanotechnology consumer
products. The most common material mentioned in the product descriptions is now silver (235).
Carbon, which includes fullerenes, is the second most referenced (71), followed by zinc (including zinc
oxide) (29), silica (31), titanium (including titanium dioxide) (38), and gold (16).
Ag
C
ZnO SiO2
TiO2
Au
Ag : 56 %
Mapping study on regulation and governance of nanotechnologies
Released: January 2009 - www.framingnano.eu
http://www.nano-technologie.pl
Which Concentration to apply ?
Quelle concentration ?
Woodrow Wilson Institute : NanoSilver Product Inventory
1cc portion from 1 ppm has a 25,000 billionth silver
each food container of Nano-silver(NS) get a 500,000 billionth silver
Each pure-silver colloid liquid & puresilver master batch contains 27.7mg/kg."
A-DO Global Co., Ltd., "Nano-Silver(NS)," http://www.adox.info/?doc=ns.php (accessed January 23, 2008).
Textiles
&
Nanoparticules d’Argent
http://www.onearth.org/article/our-
silver-coated-future
http://www.consumerscouncil.com/sit
e/Consumers_Council_of_Canada_69
/pdf/Nanotech%20report.pdf
Image of nanosilver particles from socks. Inset
demonstrates the particles contain silver
These socks were shown to contain nanosilver.
https://www.shop.eclecticsilver.net/
Benn, T. M. and P. Westerhoff (2008). "Nanoparticle
silver released into water from commercially available
sock fabrics." Environmental
Science & Technology 42(11): 4133-4139.
Environmental Impacts of Nanosilver
An ICON Backgrounder - M. Kulinowski
Published November 2008
Electronique / ElectroMénager
& Nano - Argent
Aspirateur
: Polti AS
570
Guardian Technologies
Le constructeur coréen, Samsung a annoncé fin mai
2008 la commercialisation de 4 de ses nouveaux
appareils mobiles dont le Q1 Ultra HSDPA intégrants
la technologie Silver Nano. Celle-ci a tété a été
développée exclusivement par Samsung. Ce procédé,
qui repose sur l’utilisation d’ions d’argent, permet
d’éliminer les germes et les bactéries pour diminuer les
risques de contamination.
Seo-Kwang's Silver Nano Shower (Model SKC-
1000T) uses instant voltage to create electrolysis in
order to release Silver nano water particles
(October 26th, 2008)
Samsung’s SILVER WASH is an advanced washing technology with superb bacteria killing
capabilities. Imagine 400 billion silver ions dissolved in water to make a super cleaning
solution that affects your clothes at an almost molecular level.
Its sterilizing ability of 99.99% and lasting antibacterial action will redefine your idea of
purity.
SILVER WASH utilizes 99.99% pure silver for a lasting investment for your health and
garments Effective fabric sanitization
SILVER WASH uses nano technology to electrolyze pure silver during wash and rinse
cycles. Over 400 billion silver ions are released and penetrate deep into fabric for effective
sanitization.
Enduring sanitization power
Silver Nano particles are dispensed in the washing and rinsing cycles. These silver particles
can sanitize and disinfect fabrics throughout the life of the washing machine... And not only
does its effect protect your fabrics, it also disinfects your drum and all its internal parts.
Silver Nano kit model
Silver Nano wash (different from competitive-coating)
Electrolysis of the silver
99.9% sterilization (kills 650 different types of bacteria)
Anti bacteria up to 30 days: silver nano coating on fabric
http://ww2.samsung.co.za/silvernano/silvernano/washingmachine.html
With food always fresh and ready, you'll feel better. Samsung's Silver Nano Refrigerator provides you with a germ
free environment to keep your perishables. Why take a chance on a fridge that doesn't? Feel the pleasure of a clean
place, with an advanced fridge with superb bacteria killing capabilities. Let the Silver Nano Refrigerator take you to
the edge of freshness and cut into the perfection of food purity for a taste of satisfaction.
Sophisticated nano-technology has allowed Samsung to apply a Silver Nano coating to the inner surfaces of
refrigerators for an overall anti-bacterial and anti-fungal effect. As air circulates, the coated surfaces allow the silver
ions to control the airborne bacteria. The spread of fungi and bacteria inside refrigerators is prevented providing you
with the freshest, cleanest and healthiest foods to enjoy.
http://ww2.samsung.co.za/silvernano/silvernano/refigerator.html
Colloidal silver solution is dispersed as sub-
microscopic particles (1-100nm) that can
easily penetrate cells. The silver nano
particles, when in contact with bacteria,
viruses and fungi, will suppress respiration
and adversely affect cellular metabolism,
inhibiting the cell from growing.
http://ww2.samsung.co.za/silvernano/silvernano/aircon.html
Emballage Alimentaire
http://www.bluemoongoods.com/images/food_container.jpg
NanoSilva
Integrated Antimicrobial Solutions
Engineered For Polymer Applications
FOOD AND BEVERAGE:
• PACKAGING
• PROCESS EQUIPMENT
• BULK STORAGE CONTAINERS
• PROTECTIVE CLOTHING
• REFRIGERATION EQUIPMENT
HOUSE WARES:
• FOOD STORAGE CONTAINERS
• BATHROOM ACCESSORIES
• REFUGE CONTAINERS
• KITCHEN ACCESSORIES
• COOKWARE
• FURNITURE
• KITCHEN APPLIANCES
HEALTH CARE:
• SURGICAL INSTRUMENTS
• SURGICAL EQUIPMENT
• MEDICAL IMPLANTS
• PACKAGING
• SURGICAL APPAREL/GLOVES
• MEDICAL DEVICES
• WOUND CARE
Nanocoated Film as a Bacteria Killer
Source:Nanowerk (23 Janvier 2009)
Researchers at the Institute for Chemical and Bioengineering of ETH Zurich,
Switzerland, have developed a plastics film made with silver and calcium phosphate
nanoparticles that is lethal to bacteria and self-disinfecting. The combination of these two
substances results in a product that is 1000 times more lethal to Escherichia coli than
conventional silicon-based silver preparations. The silver, which kills the bacteria, is only
released when the bacteria consume the calcium substrate and cause it to disintegrate.
http://www.nanowerk.com/news/newsid=8997.php
The calcium phosphate particles, 20 to 50
nanometres in size, are absorbed by the
micro-organisms as food and are thereby
disintegrated. This releases thousands of
tiny silver particles measuring 1 to 2
nanometres which the researchers had
coated onto the calcium nutrient.
The silver is thus used in a targeted manner,
and in a controlled amount, saving costs and
incurring less stress on the human body.
The film, which is already being
manufactured, can be used by
hospitals in areas that are hotspots
for germ transmission, such as
door handles, beds, and sanitary
equipment. The film is not effective
indefinitely and must be replaced
periodically.
Films, Vernis, Peintures
http://www.e-p-g.de/
http://www.atheco.ch/joomla/files/FlyerNaturefranzklein.pdf
Ahead of flu season, Hong Kong’s MTR Corporation spray surfaces
passengers often touch – such as grab poles inside the trains, escalator
handrails and buttons on ticket machines – with a nano silver-
titanium dioxide coating.
Applications
Cosmétiques
Médicales
Et Sanitaires
In 1990s, silver was introduced as a colloidal form
(i.e. silver nanoparticles) in ointments that could be
applied to open wounds to kill bacteria very
effectively.
S. Arora, J. Jain, J.M. Rajwade, K.M. Paknikar - Toxicology Letters 179 (2008) 93–100
http://nanover.en.ecplaza.net/4.asp
http://www.nanogist.co.kr/
Nano Silver Hand Sanitizer
Nano Silver Hand sanitizer combines
Nano Silver with a special blend of
moisturizers to kill wide spectrum of
microorganisms those also known as
microbes, germs, bacteria, fungi on your
hands without need for water or
towels and leave them feeling soft and
refreshed.
. Reduces the risk of health care-acquired
infections by helping to protect against a
wide range of germs that
may cause disease.
. Can be used to supplement handwashing
and when soap and water aren't readily
available.
. Once applied, kills all types of bacteria
and eColi viruses within 15 seconds and
keeps your hands clean and soft.
Background: Treatment of acute burn wounds with silver sulfadiazine (SSD) has raised concern about potential silver
toxicity. Numerous adverse reactions and side effects have been reported and an increasing resistance to SSD, especially in
Pseudomonas strains, have motivated researchers to search for an alternative wound dressing.
Methods: Recently, a silver-coated wound dressing Acticoat (Smith & Nephew, Inc.) has become available for use in burn
patients. It is a three-ply dressing, consisting of an inner rayon/polyester absorptive core between two layers of silver-coated,
high-density polyethylene mesh. In a moist environment, the nanocrystals of silver are released and improve the microbial
control in the wound.
Results: After 1 week of local treatment with Acticoat in a young, previously healthy 17-year-old boy with 30% mixed
depth burns, hepatotoxicity and argyria-like symptoms, a grayish discoloration of the patient's face, appeared.
The silver levels in plasma (107 μg/kg) and urine (28 μg/kg) were clearly elevated, as well as the liver enzymes.
As soon as the local application of Acticoat was aborted, the clinical symptoms and liver enzymes returned to the
normal values.
Conclusions: This is the first report on silver toxicity in a patient with 30% burns who received Acticoat for local treatment.
Due to substantial experiences with adverse SSD reactions and side effects, it is appropriate to keep the possibility of a toxic
silver effect in burn patients treated with Acticoat silver-coated wound dressing in mind. The silver levels in plasma and/or
urine should be monitored.
Silver-Coated Dressing Acticoat Caused Raised Liver
Enzymes and Argyria-like Symptoms in Burn Patient
[Case Report]
Trop, Marija MD; Novak, Michael MD; Rodl, Siegfried MD; Hellbom, Bengt MD; Kroell,
Wolfgang MD; Goessler, Walter PhD
The Journal of Trauma: Injury, Infection, and Critical Care:Volume 60(3)March 2006pp 648-652
Paul Karason's skin turned blue after he used
colloidal silver to ease his ailment
http://abcnews.go.com/Health/MedicalMysteries/story?id=5
489997&page=1
► Cycle de Vie
Toxicité
EcoToxicité
Etat des Connaissances
Nano-silver contributes 0.3-15% to the total Ag flow
- Free ionic Ag+ is extremely toxic (PNECWater 0.1 ng/l, PNECsediment 2 ng/l)
- Predicted dissolved Ag: 40-320 ng/l
- BUT: Silver is strongly complexed
- Complexed Ag is much less toxic
Source : Bernd Nowack
http://www.wsl.ch/events/research_seminar/rs_2009/pres-nowack.pdf
In 2010, biocidal plastics and textiles are predicted to account for up
to 15% of the total silver released into water in the European Union.
Blaser, S. A., M. Scheringer, et al.
Science of the Total Environment 390(2-3) (2008) 396-409.
Nanosilver
Nanosilver coatings are known for their antimicrobial action and are increasingly being used in a range of products
such as wound dressings, urinary catheters, self-cleaning clothes, toothpastes, and washing machines16. Nanosilver is
anticipated to play a major role in many different coatings from food packaging to wall/roof coverings.
Although the principle is based on the slow formation and release of Ag ions,
there is little information on the influence of wear on these products
and the release of Ag nanoparticles or ions from coatings into the
surrounding media.
Although the toxicology of Ag ions is well described, it is mostly based on acute spills and high concentrations. From
an environmental and health perspective, nanosilver could be dangerous since general exposure to Ag may damage
aquatic environments, which are highly sensitive.
This concern has led some waste treatment organizations in the US to protest at its use in washing machines. Both
TriTAC (a technical advisory group for Publicly-Owned Treatment Works in California) and the National Association
of Clean Water Agencies (NACWA) submitted letters of concern to the US Environmental Protection Agency in 2006.
There is much less data on the effects of chronic exposure to low levels of Ag ions and
nothing on Ag nanoparticles, which could act as a carrier system for local release.
Paul J. A. Borm, David Berube
NanoToday - FEB-APR 2008 | VOLUME 3 | NUMBER 1-2
Stabilité / Usage ???
http://juicygirl.en.ec21.com/260_Den_Nano_Silver_Far--1274134_1274150.html
Stabilité / Usage ???
" AgActive socks ship with at least a hundred times more silver in
them than they actually need to work. This silver ‘dust’ is invisible but
extremely effective at disinfecting shoes of bacteria and fungi. When you first wash the
socks, the silver levels will drop to normal. Don’t miss out on the opportunity to take
advantage of the extra dust they
are shipped with: wear the socks in every pair of problem shoes you own before you
first wash the socks.
The extra dust will drop out and clean the inside of your shoes.
Remember: you can wear AgActive socks in a new pair of shoes every day and they
won’t become smelly. You don’t need to wash them unless they pick up visible
dirt." (retrieved 09.10.2007)
AgActive, "How to get the most out of your socks," http://www.agactive.co.uk/
(accessed June 11, 2007).
TEM and EDX analysis of the colloids in the wash water of sock 1a (Figure 4) indicated the presence of silver material
with diameters from one to a few hundred nm. These particles are in the same size range and are irregularly shaped
like the particles in the SEM image of the sock 1a material. Thus, at least some of the n-Ag is released into the wash
water as nanoparticles; not just as dissolved ionic silver. Table 2 summarizes the colloidal and ionic characterization of
the silver leached into the wash waters. Very little silver was separated by filtration into the size range of 20-100 nm.
For sock 1b, about 70-90% of the silver was characterized as ionic by the ISE depending on the number of washings,
which suggests that 75-100 μg/L of n-Ag may be present in the wash waters. Therefore, it should not be assumed that
all if the silver initially released from socks is in the dissolved ionic form.
The first wash of sock 3 released nearly all silver as colloidal, as confirmed by the agreement of the filtration and ISE
data. Subsequent washes of sock 3 contained increasing amounts of ionic silver. Thus, the ultrapure water in which
these experiments were conducted may be corrosive.
In experiments using commercial n-Ag (Aldrich) in ultrapure water, the ionic silver in solution increased over time as
measured by ISE. This suggests that n-Ag is oxidized into a dissolved ionic form when subjected to prolonged
exposure in water.
Silver Characterization of the Sock Wash Solutions
Troy M. Benn and Paul Westerhoff
Environ. Sci. Technol., 2008, 42 (11), pp 4133–4139
EPA (USA) to Regulate NanoProducts sold as Germ – Killing
Source : R. Weiss - Washington Post – 23 November 2006
Back in February, Samsung, one of the world's largest appliance and
electronics manufacturers, introduced the world's first washing machine to
employ what Samsung calls "SilverCare™ Technology". Samsung claims that
the technology allows "over 100 quadrillion silver ions to penetrate deep into
the fabric to sanitize clothing without the need for hot water or bleach.
Samsung countered that only an accumulated amount of
0.05 grams of silver are released per machine
and year, while the released silver-ions quickly bind to non-nano-sized
structures in the water. Therefore, the thread should be minimal.Any toxic
effect of nanoparticles has to be considered together with the kind, size and
modification of the particles. General predictions on the toxicity of
nanoparticles are not possible.
BUND wants Samsung to stop selling the new washer in Germany. Similar
pressure by consumer activist organizations in Sweden already forced
Samsung to take it off the market there. Consumers who already bought the
appliance were told by Samsung to use the silver cycle "carefully
Some products combine different kinds of nanotechnology, such as the
Samsung Nano SilverSeal refrigerator
“Samsung has rolled out a line of fridges and washing machines that use
nanocoatings to prevent nasty bugs from growing. Specks of silver, as
small as one nanometer across, are used to coat surfaces. These
nanoparticles are so electrically active that they inhibit the growth of
harmful bacteria and fungs. In its fridge, Samsung used the nanosilver in
the deodorizer unit and water dispenser to sanitize the air and water that
passes over them.”
Cycle de Vie
Toxicité
► Eco-Toxicité
Etat des Connaissances
Nano-silver contributes 0.3-15% to the total Ag flow
- Free ionic Ag+ is extremely toxic (PNECWater 0.1 ng/l, PNECsediment 2 ng/l)
- Predicted dissolved Ag: 40-320 ng/l
- BUT: Silver is strongly complexed
- Complexed Ag is much less toxic
Source : Bernd Nowack
http://www.wsl.ch/events/research_seminar/rs_2009/pres-nowack.pdf
In 2010, biocidal plastics and textiles are predicted to account for up to 15% of the total
silver released into water in the European Union.
Blaser, S. A., M. Scheringer, et al.
Science of the Total Environment 390(2-3) (2008) 396-409.
Emerging nanomaterials are of great concern to wastewater treatment utilities and
the environment. The inhibitory effects of silver nanoparticles (Ag NPs) and other
important Ag species on microbial growth were evaluated using extant respirometry
and an automatic microtiter fluorescence assay. Using autotrophic nitrifying
organisms from a well-controlled continuously operated bioreactor,
Ag NPs (average size = 14 ± 6nm), Ag+ ions (AgNO
3
), and AgCl colloids (average size
= 0.25 mm), all at 1mg/L Ag, inhibited respiration by 86 ± 3%, 42 ± 7%, and 46 ± 4%,
respectively.
Based on a prolonged microtiter assay, at about 0.5mg/L Ag, the inhibitions on the
growth of Escherichia coli PHL628-gfp by Ag NPs, Ag+ ions, and AgCl colloids were
55 ± 8%, 100%, and 66 ± 6%, respectively.
Cell membrane integrity was not compromised under the treatment of test Ag species
by using a LIVE/DEAD BaclightTM bacterial viability assay.
However, electron micrographs demonstrated that
Ag NPs attached to the microbial cells, probably causing cell wall pitting.
The results suggest that nitrifying bacteria are especially susceptible to inhibition by
Ag NPs, and the accumulation of Ag NPs could have detrimental effects on the
microorganisms in wastewater treatment.
The inhibitory effects of silver nanoparticles, silver ions,
and silver chloride colloids on microbial growth (1/2)
Okkyoung Choi, Kathy Kanjun Deng, Nam-Jung Kim, Louis Ross Jr., Rao Y. Surampalli, Zhiqiang Hu
WATER RESEA RCH 42 (2008 ) 3066 – 3074
NanoSilver was more toxic than silver ion
or silver colloids at the same Ag concentration
Okkyoung Choi, Kathy Kanjun Deng, Nam-Jung Kim, Louis Ross Jr., Rao Y. Surampalli, Zhiqiang Hu
WATER RESEA RCH 42 (2008 ) 3066 – 3074
Nitrification inhibition inferred from
the decrease of specific oxygen uptake
rate (slope of curve A) in the presence
of Ag NPs, as compared with control
(curve B) after an aliquot of
ammonium nitrate was injected
individually at approximately 100 s.
The inhibitory effects of silver nanoparticles, silver ions,
and silver chloride colloids on microbial growth (2/2)
At 1 mg/L Ag in the nitrifying suspension, the inhibitions by
Ag NPs, Ag+ ions, and AgCl colloids were 86±3%, 42±7%, and
46±4%, respectively. Of all the Ag species tested, Ag NPs
presented the highest inhibition on nitrifying bacterial growth.
One ounce (nano) = one ton (micro)
Another problem with regulating nanosilver is figuring out how to quantify its risks.
Typically, pollution is regulated by the amount of contaminant in the environment by
weight or volume. But these may not be useful measures of the effects – either positive or
negative – of nano-sized particles. The reactive part of silver is on its surface, and nano-
sized particles have thousands or even millions of times the surface area of bulk material.
That means one ounce of nanosilver dust could have the same surface area as one ton of
bulk silver, depending on the particle size.
Eventually, regulations might have to be based on number of particles per volume or even a
calculated surface area.
http://www.nanowerk.com/news/newsid=6190.php
Surface Effect ( ≠ mass effect)
Distribution size importance
Nanosilver
A strong argument for the introduction of Ag is
that bacteria cannot develop resistance to it as they tend to do against antibiotics.
Not so, according to some who believe that Ag resistance can be accomplished relatively fast
– comparable to susceptibility effects to antibiotics.
They claim that Ag resistance is most easily developed in bacteria with already documented
resistance mechanisms to antibiotics, such as methicillin-resistant Staphylococcus aureus
(MRSA) and others.
Ag resistance associated with antibiotic resistance has been observed in
isolated bacteria from birds and in salmonella. There are Ag-resistant bacteria in our
mouths, which may possibly be related to the Ag in amalgam fillings.
Ag-resistant bacteria have also been found in nature, food, intestinal bacteria from different
geographic locations, and hospitals.
A systematic review of clinical trials with Ag-coated urinary catheters reveals that few
studies have addressed secondary bloodstream infection, mortality, costs, or microbial
resistance, although some studies have revealed no Ag resistant pathogens within a two-year
trial period.
Résistance Bactérienne
Paul J. A. Borm, David Berube
NanoToday - FEB-APR 2008 | VOLUME 3 | NUMBER 1-2
The risk quotients (PEC/PNEC) for CNT and nano-Ag were much smaller than one,
therefore comprising no reason to expect adverse effects from those particles.
Mueller, N. C. and B. Nowack (2008
Environ. Sci. Technol. 42(12) (2008) 4447-4453
Because a complete characterization of the toxicity of environmentally relevant silver
species is lacking, only a limited risk assessment is possible at this time.
However, our study indicates that PEC/PNEC ratios greater than 1 cannot be ruled out for
freshwater ecosystems, in particular sediments.
No risk is predicted for microbial communities in sewage treatment plants.
Blaser, S. A., M. Scheringer, et al.
Science of the Total Environment 390(2-3) (2008) 396-409
The authors estimate that silver concentrations reaching a sewage treatment plant would
have to exceed 2900 ppb (salt water) or 4250 ppb (fresh water) for the effluent to fail EPA
standards for treated water. These concentrations are 3000 times higher than levels
typically measured in a sewage treatment plant.
However, increased use of nanosilver in consumer products may result in sludge that is
too concentrated to use legally as fertilizer.
Benn, T. M. and P. Westerhoff (2008). "Nanoparticle silver released into water from commercially available sock
fabrics." Environmental Science & Technology 42(11): 4133-4139
Impact faible OU accumulation sédiments, stations d’épuration ?
Emission / Impact sur l’environnement
Informations Contradictoires !
Réglementation
(Etiquettage, Traçabilité)
Clavier d’Ordinateur
Samsung a dévoilé son modèle SCH-V600, version affinée du SCH-V500, que l'on pouvait
voir lors du 3GSM. Cette série se distingue par son écran pivotant passant à la volée du
mode portrait au mode paysage. Dans le cas du V600, si les dimensions sont plus réduites
par rapport au V500, le clavier conserve toute son ergonomie.
Mais la nouveauté du SCH-V600 consiste en son revêtement contenant des particules
d'argent et agissant comme un agent anti-microbien.
http://www.xelopolis.com/news/breve_482_%5Basie%5D+samsung+sch-
v600+ecran+horizontal+peinture+anti-bacterienne.html
http://www.presence-pc.com/actualite/netbook-valentin-samsung-33223/
Points intéressants de cette machine, le clavier et la batterie : le premier
est protégé contre les bactéries grâce à la technologie Silver Nano,
http://www.pureplushy.com/
Benny the Bear, and the case of the disappearing nanoparticles
“the first company of its kind, that through the use of a patented technology, is offering
anti-mite anti-mold and anti-microbial plush toys. The technology involves infusing silver, a
natural anti-mite, anti-mold and anti-microbe agent, nanoparticles—25 nanometers thick,
about one 200 thousandth of a human hair—inside memory foam.”
http://community.safenano.org/blogs/andrew_maynard/archive/2007/12/15/benny-the-bear-and-the-case-of-the-
disappearing-nanoparticles.aspx
Benny is the latest in a series of products where “nano” has mysteriously disappeared from the
marketing information. That makes it difficult for consumers to make informed choices. It
prevents a clear picture emerging of where engineered nanomaterials are being used (and in
what quantities). It confounds attempts to study the potential impact of commercially relevant
materials (par www.archive.org)
W. de Jong – RIVM – Nov. 2009 – NanoSafety for Success Dialog
Nano Silver (n-Ag)
Plus de 500 produits sur le marché
(Many Products yet on the market (> 500))
Quantité x 500 pour les NanoProduits nAg
n Ag Products : Ag quantity x 500
Efficacité : x 1.000
Etiquettage ( Ag+, np Ag ??)
Nano Labelling ?? (ionic Ag
+
or nanoparticle Ag)
EcoToxicité ≠ NanoEcoToxicité (dépendant du produit)
Toxicity ≠ Nano Toxicity !!!
Et Nano Tox ≠ for same product label
Cycle de Vie (Rejet dans l’Environnement)
Incertitude sur les effets
(quantité relarguée, np ou Ag+, toxicité)
Nano life cycle : not only function of initial state
(1-x) % n-Ag + x% Ag
+
x% = Fonction life cycle (washing and washing media, washing number)
Conclusions Partielles
Eric.Gaffet@utbm.fr